Drawing projector for reproducing curves

ABSTRACT

This drawing apparatus has adjustable mechanism for guiding a scriber to make curved lines and closed areas of different shapes over a wide variety. The adjustments are graduated and can be set to reproduce a predetermined curve or closed area. An element that moves in a circle on an adjustable base is connected with a scriber by a beam which is angularly movable and also movable in the direction of its length. This provides a simple and accurate mechanism for projecting the scriber along a desired path.

, United StatesPatent 1191 Yozzo June 28, 1974 DRAWING PROJECTOR FOR REPRODUCING CURVES [76] Inventor: Dominic F. Yozzo, Tappan, NY. 221 Filed: June 26, 1973 [2!] Appl. No.1 373,657

[52] US. Cl. 335/27 R, 33/30 R [51] Int. Cl B43l 11/04 [58] Field of Search 33/18 R, 18 B, 18 C, 27 R,

33/27 B, 30 R, 30 G, 27 K, 30 B, 31, 30 F,

[56] References Cited UNITED STATES PATENTS l84,493 I1/I876 Anderson 33/25 E 73 1 ,0l8 6/l903 Carlton 33/30 R FOREIGN PATENTS OR APPLICATIONS 868,469 4/1971 Canada 33/30 R Primary Examiner-Harry N. Haroian Assistant ExaminerJohn W. Shepperd Attorney, Agent, or Firm -Sandoe, Hopgood & Calimafde [5 7 1 ABSTRACT This drawing apparatus has adjustable mechanism for guiding a scriber to make curved lines and closed areas of different shapes over a wide variety. The adjustments are graduated and can be set to reproduce a predetermined curve or closed area. An element that moves in a circle on an adjustablebase is connected with a scriber by a beam which is angularly movable and also movable in the direction of its length. This provides a simple and accurate mechanism for projecting the scriber along a desired path.

10 Claims, 14 Drawing Figures PATENTEDJUHZB m4 3 20.245

sum 1 n? 2 FIG. I. 44

I n l I l l 1 I 4 -52- TENTEnJuazs I974 $820,245

sum 2 or 2 FIG] N H. Q m f 'l I 1 DRAWING PROJECTOR FOR REPRODUCING CURVES I BACKGROUND AND SUMMARY OF THE INVENTION The apparatus of this invention moves a scriber along paths that are the resultant of combinations of straight line, arcuate and angular movements of the propelling mechanism. It can produce ornamental designs such as have been made by prior drawing devices, but in addition to such ornamental designs, the apparatus of this invention can be adjusted to reproduce lines and areas of practical utility such as predetermined curves and correlations of curves with other lines, for example non-circular curved lines that are'tangent to parallel straight lines located at given distances from one another.

This invention can also be used to draw cross sections for lens designs, and other closed areas having peripheral limits that are convex or concavo-convex. An important feature of the invention is that it can be easily and accurately adjusted to reproduce preselected lines and/or shapes.

The apparatus is simple and includes few parts. A scriber is carried by a beam which has both angular and endwise movement about a pivot.Motion is imparted to the beam by an adjustable length link element that moves about an axis bearing which is adjustable in its spacing from the beam pivot. All adjustments are made along scales so-that any curve or area can be reproduced by appropriate adjustment along the scales.

Other-objects, features and advantages of the invention will appear or be pointed out as the description proceeds.

BRIEF DESCRIPTION OF DRAWING In the drawing, forming a part hereof, in which like reference characters indicate corresponding parts in all the views:

FIG. 1 is an isometric, assembly view of the apparatus of this invention and shows the apparatus in operation DESCRIPTION OF PREFERRED EMBODIMENT FIG. 1 shows a work surface 10 over which a scriber I2 is moved by a beam 14 to which the scriber is rigidly connected. The scriber I2 is shown drawing a curve 16 on the work surface 10. The beam 14 has a slot 18 extending lengthwise of the beam and there is a pivot 20 which extends through the slot 18.

The pivot connection between the beam 14 and the pivot 20 will be described in connection with FIG. 6.

Continuing with the description of FIG. I, the beam 14 extends beyond the pivot 20 and connects with a link element 22 comprising a disc 24 with a slot therein,

and a pin 26 which extends through the slot in the disc 24 and through the slot 18 in the beam 14; and which also comprises clamps 28 and 30 (FIG. 5 These clamps 28 and 30 will be described in detail in connection with FIGS. 4 and 5.

FIGS. 1 and 2 show the disc 24 supported from a frame 34 by an axis bearing 36. The pin 26 is adjustable lengthwise along a slot 38 in the disc 24. This slot 38 is shown as extending radially, but it will be understood that it can extend in other directions so long as it has a radial component and if extended in such other direction, the slot can be longer so that adjustments of the pin 26 lengthwise of the slot will be along greater distances for the same radial adjustment and thus make the adjustment cover a longer distance for the same change in radius.

There is a scale 40 along the slot 38 for determining the spacing of the pin 26 from the axis bearing 36. This distance, measured from the centers of the pin 26 and axis bearing 36 is the effective length of the link ele ment 22. When the apparatus is in operation, the pin 26 is clamped at a fixed location along the slot 38 and the pin 26 is held in a fixed location along the beam 14 by the clamp 28 (FIG. 1). However, the pin 26 is free to rotate in the clamp 28 and the upper part of the pin 26 extends above the level of the beam 14 so as to provide a handle 42 by which the apparatus can be operated by one hand 44 of an operator.

The disc 24, the frame 34 and the base on which the frame 34 rests are preferably made of clear, hard plastic material which is transparent so that any lines or designs on which the apparatus is placed can be seen through the disc, plate and base.

Referring to FIG. 2, the handle 42 can be rotated from the full line position shown in FIG. 2 to the dotted line position. This represents an angular movement of the disc 24 about the axis bearing 36 of somewhat more than This movement will move the beam 14 endwise with respect to the pivot 20 and will at the same time rock the beam 14 through the angle indicated by the dimension arrow 48. The scriber will be moved, by this combination endwise and angular movement of the beam 14, from the full line position shown in FIG. 2 to the dotted line position. The scriber will extend the line 16 from the full line portion shown in FIG. 2 to the extended length indicated by the dotted lines. As the disc 24 continues its rotation to complete a full circle of 360, the scriber 16 will describe a closed area. When the invention is to be used for drawing lines, rather than enclosing areas, only a portion of a circle is described by the handle 42.

The axis bearing 36 can be moved closer to or further from the pivot 20 by sliding the frame 34 along a base 50 on which the frame 34 rests. There are guides 52 at both sides of the base 50 for preventing movement of the frame 34 in any direction except movement toward and from the pivot 20 which is fixed to the base 50. Scales 54 along the guides 52 cooperate with indicators 56 for determining the spacing of the axis bearing 36 from the pivot 20. The frame 34 fits snugly between the guides 52 and friction of the frame 34 against these guides 52 and on the surface of the base 50 holds the frame 34 in any adjusted position and no clamping means are necessary.

From the description thus far it will be apparent that the endwise movement of the beam 14, during a complete revolution of the disc 24, will be equal to twice 3 the length of the distance from the center line of the axis bearing 36 to the center line ofthe pin 26. The axis bearing 36, pin 26, disc 24 and the associated connecting parts comprise a'pivoted link connecting the beam 14 with the axis bearing 36; and the length of this link is adjustable as has been already explained.

The angular movement of the beam 14 about the pivot is determined partly by the spacing between the pin 26 and the axis bearing 36; but also and to a greater extent by the spacing of the axis bearing 36 from the beam pivot 20. The length of the beam 14 can also be adjusted by adjusting the clamp 28, which carries the pin 26, along the slot 18 of the beam 24. It is this combination of adjustments that gives the invention such an extremely wide range of curves and areas which it can draw and enclose.

There is a scale 60 (FIGS. 3 and 4) along the side of the beam 14. This scale is used for determining the location of the pivot 20 along the length of the beam 14 and also for determining the setting of the clamp 28 which carries the pin 26.

' FIGS. 3 and 6 show the pivot 20 and the way in which it is assembled with the base 50- and the beam 14. The I tions 68 which extend down'the sides of the shield 66.

A cutout section 70 on one side of the shield 66 exposes the scale 60 and there is an indicator 72 on the top of the shield 66 for indicating the position of the beam 14 endwise with respect to the pivot 20.

The beam 14 rests on the collar 64 and is held down against the collar with a yielding pressure exerted by a spring 74 which is compressed between the top of the shield 66 and a nut 76 that is used for adjusting the pressure of the spring 74 against the shield 66 and the resulting pressure of the beam l4against' the supporting collar 64. I

FIG. 4 shows the disc 24 provided with scale indications 78 around its circumference. These scale indications are omitted in FIGS. 1 and 2 because of the small scale of the drawings. The scale indications 78 are used in connection with an indexing line 80 on the base 50 to show the angular position of the disc 24 and the corresponding angular position of the link formed by the connecting structure between the axis bearing 36 and the pin 26.

The clamp 28 includes a bolt 84 which extends through the slot 18 in the beam 14. This bolt 84 has a head 86 which bears against the underside of the beam 14 on opposite sides of the slot 18. A nut 88 screws over the upper end of the bolt 84 and clamps a plate 90 of the clamp 28 against the upper side of the beam 14. This holds the clamp '28 in fixed relation with respect to the beam 14.

The plate 90 has side walls 92, one of which is shown in FIG. 4; and there is a cutout 94 in the side wall 92 for exposing the scale 60 on the side of the beam 14. An indexing line 96 on the plate 90 cooperates with the scale 60 to indicate the location of the clamp 28 along the length of the beam 14.

A bushing 98 has its lower end screwed into the clamp 28 and locked in position by a lock nut 100. The pin 26 extends upwardly through the bushing 98 and is fully rotatable in the bushing 98, the latter being in a fixed position on the clamp 28. The upper end of the pin 26 is gripped by a handle portion 42 as already explained.

The lower end of the pin 26 has a countersunk block portion 30 (FIG. 5) which fits into the slot 38. This slot 38 has a tapered cross section corresponding to the taper of the block 30 and the block 30 is pulled up into clamping relation with the tapered sides of the slot 38 by a clamping nut 104. The apparatus is operated by moving the handle portion 42 (FIG. 4) in a direction to rotate the disc 24 either clockwise or counterclockwise as required to obtain the desired line which the scriber is to draw.

The construction of the invention has been described, but some examples of the operation will explain the use of the invention more fully. In explaining the operation the adjustment of the machine for different curves will be described and this will entail certain adjustments of beam length, link length and spacing of the beam pivot from the center of rotation of the link. In the discussion that follows these adjustments will be designated as follows:

BE= length of beam 14 from scriber .12 to center of pin 26.

PC distance of pivot 20 from axis bearing 36.

CE length of effective link between pin 26 and axis bearing 36 measured on centers.

These letter designations are indicated in FIG. 2 for more convenient reference.

FIG. 7 shows the various dimensions that determine the classification of the curves drawn; and examples of some of the curves are shown in FIGS. 8 14.

l distance from point H to the line NS m distance from the line NS to the point Q along the line HQ n distance from the line N,S to the point Q l, distance from point H, to the line NS m, distance from line NS to point Q t= distance along the line NS to the line H t, distance from N to line H O,

f distance from points to'point O. This distance is the same as from the point N to the point Q e extension of the distance x with certain types of curves FORM CLASSIFICATION TABLE closed area The y axis does not cut or touch the x axis, but its mid-point would he crossed by an extension of the x axis to point e in FIG. ll.

The closed areas outlined by the invention have the enclosing curve analyzed as shown in FIG. 7. The points H and Q on the curve in FIG. 7 are the most widely separated points on the curve and they are on opposite ends of a bisector of the area, the curve being symmetrical about the line HQ. The points 1-1 and Q1 are at the intersection of the curve with a line l-l Q which is parallel to the line I-IQ and which is located midway between the line HQ and a point N at the top of the curve.

The points N and S are the points on the curve that are most widely separated in a direction normal to the symmetrical line HQ.

Two other significant points on the curve are N and 8,. These are the points reached by the scriber as it travels 90 to either side of the center line HQ about which the curve is symmetrical. The line N 5, intersects the line HQ and the distance from this intersection to the point is significant. I

The length of the line NS is indicated by the letter y. The length of the line N 5, is indicated by the letter y,. The length of the lines HQ and H 0 are indicated by the letters x and x respectively.

Segments of these lines in FIG. 7 are indicated as follows:

For the y axis t, t,

For the x axis l, m

For the X axis 1 m,

In all forms x axis bisects y axis. At the same time, however, y axis divides x axis unequally except in the case of an ellipse or oval when x and y axis bisect each other.

FIG. 8 shows a curve which is form type A. The significant factors for this curve are as follows:

With the distances BE and CE selected as follows: BE 13% inches/ and CE 1% inches, the distance PC can be computed from the following formula:

Projector Form .r Axis Segments BE=14" .r=l% l=1%" CE=%" y=9%" m =0 The adjustment for PC is figured from the formula below:

FIG. 11 shows a form type F curve. The factors for this curve are as follows:

Projector Form x Axis Segments BEFMA F2" .x=2" 35.11 y =l2/2 extensiog 3/l6" The adjustment for PC is computed from the form type F formula as indicated below:

P B/y/x 1 P= 14k/(12'r/2) +1 P 2" FIG. 12 shows an oval. The selected oval is indicated by the points A B E D. The oval was obtained by adjusting the machine for the curve A B C D. f and g are points where the curve departs from that of an oval and the oval A B E D was obtained by turning the paper around after drawing slightly more than half of the oval and before the scriber had scribed the curve f C g.

FIG. 13 shows a parabolic type of curve where the requirements were that the point 2 be equidistant from the points 1 and 3. The required adjustments were as follows:

BE 12 inches CE 1% inches PC 6 9/16 inches FIG. 14 shows the way in which two existing parallel lines through the points N and S and spaced by the distance y were joined by a curve which would be tangent to the parallel lines at its point of juncture with the lines and which would have a distance m equal to 1 /2 inches and a distance f equal to 1% inches, the space between the parallel lines being 2 inches. With a beam length (BE) of 12 inches, the adjustments for the values CE and PC were computed by formulae as follows:

Two existing parallel lines can also be connected by a non-symmetrical curve of predetermined factors using appropriate formulas.

The preferred embodiment of the invention has been described and some of the ways in which the invention has'been used have also been described; but it will be understood that the number of curves which can be drawn by the apparatus are infinite, though they fall into certain designated classes as explained in the specification. Changes and modifications can be made in the construction and some features can be used in different combinations without departing from the invention as defined in the claims.

What is claimed is:

1. Apparatus for reproducing curved lines including in combination a beam, a pivot, the beam having a slot therein extending lengthwise of the beam and through which the pivot extends in a direction substantially normal to the direction of extent of the slot whereby the beam is movable with respect to the pivot both angularly and in the direction of the length of the beam, a scriber carried by the beam in a position to travel over a work surface as the beam moves with respect to the 7 pivot, a frame that holds the pivot in a relatively fixed position during the movement of the scriber over said work surface, a link element connected with the beam, an axis bearing connected with the link element at a location spaced from the connection of the link element to the beam, the link element being made of parts that are adjustable by movement with respect to one another to change the length of the link element between the axis bearing and the connection of the link to the beam, and means for moving the link element angularly about said axis bearing to impart angular and sliding movement to the beam with respect to the pivot.

2. The apparatus described in claim 1 characterized by a scale along one of the movable parts of the link element for indicating the effective adjusted distance between the center of angular movement of the link on the axis bearing and the center of angular movement of the link and beam.

3. The apparatus described in claim 1 characterized by a frame on which the axis bearing is supported, the link element comprising a disc with a center bearing that rotates on the axis bearing, a block that slides along a slot in the disc, said slot extending in a direction .having a radial component, means for clamping the block at desired locations along the slot, the block being a part of the link element that connects with the beam.

4. The apparatus described in claim 3 characterized by the disc and frame having a scale on one of them and a position indicator on the other for indicating angular positions of the disc, a base for placing on a support,

' the pivot being connected to the base as a unitary part thereof, the disc-supporting frame being located on the base and slidable along the base toward and from the pivot, guides on the base for the frame, and scales for indicating the spacing of the axis bearing from the pivot as the position of the frame is adjusted along the guides.

5. Apparatus for reproducing curved lines including in combination a beam, a pivot, the beam having a slot therein extending lengthwise of the beam and through which the pivot extends in a direction substantially normal to the direction of extent of the slot whereby the beam is movable with respect to the pivot both angularly and in the direction of the length of the beam, a scribercarried by the beam in a position to travel over a work surface as the beam moves with respect to the 8 element angularly about the axis bearing to impart angular and sliding movement to the beam with respect to the pivot.

6. The apparatus described in claim 5 characterized by the means for moving the link element angularly about the axis bearing being a handle extending upward from the connection of the link element to the beam,

the handle being in axial alignment withthe angularly movable connection of the link element to the beam.

7. The apparatus described in claim 5 characterized by means for'adjusting the length of the beam between the center points of the scriber and the connection of the link element with the beam.

' 8. The apparatus described in claim 5 characterized by the beam being slotted throughout substantially its entire length to provide the sliding movement of the beam in the direction of its length with respect to the pivot and for the adjustment of the connection of the link element along the length of the beam, and the scriber and the link element being on different sides of the pivot along the length of the beam.

9. The apparatus described in claim 5 characterized by a frame on which the axis bearing is supported, the link element comprising a disc with a center bearing that rotates on the axis bearing, a block that slides along a slot in the disc, said slot extending in a direction having a radial component, means for clamping the block at desired locations along the slot, the block being a part of the link element that connects with the beam, the disc and frame having a scale on one of them and a position indicator on the other for indicating angular positions of the disc, a base for placing on a support, the pivot being connected with the base as a unitary part thereof, the disc-supporting frame being located on the base and slidable along the base toward and from the pivot,- guides on the base for the frame, scales along the guides for indicating the spacing of the axis bearing from the pivot as the position of the frame is adjusted along the guides, the beam being slotted throughout substantially its entire length to provide for sliding movement of the beam in the direction of its length with respect to the pivot and for the adjustment for the connection of the link element along the length of the beam, and the scriber and the link element being on difi'erent sides of the pivot lengthwise of the beam.

by the base and other parts of said rest of the apparatus. k 

1. Apparatus for reproducing curved lines including in combination a beam, a pivot, the beam having a slot therein extending lengthwise of the beam and through which the pivot Extends in a direction substantially normal to the direction of extent of the slot whereby the beam is movable with respect to the pivot both angularly and in the direction of the length of the beam, a scriber carried by the beam in a position to travel over a work surface as the beam moves with respect to the pivot, a frame that holds the pivot in a relatively fixed position during the movement of the scriber over said work surface, a link element connected with the beam, an axis bearing connected with the link element at a location spaced from the connection of the link element to the beam, the link element being made of parts that are adjustable by movement with respect to one another to change the length of the link element between the axis bearing and the connection of the link to the beam, and means for moving the link element angularly about said axis bearing to impart angular and sliding movement to the beam with respect to the pivot.
 2. The apparatus described in claim 1 characterized by a scale along one of the movable parts of the link element for indicating the effective adjusted distance between the center of angular movement of the link on the axis bearing and the center of angular movement of the link and beam.
 3. The apparatus described in claim 1 characterized by a frame on which the axis bearing is supported, the link element comprising a disc with a center bearing that rotates on the axis bearing, a block that slides along a slot in the disc, said slot extending in a direction having a radial component, means for clamping the block at desired locations along the slot, the block being a part of the link element that connects with the beam.
 4. The apparatus described in claim 3 characterized by the disc and frame having a scale on one of them and a position indicator on the other for indicating angular positions of the disc, a base for placing on a support, the pivot being connected to the base as a unitary part thereof, the disc-supporting frame being located on the base and slidable along the base toward and from the pivot, guides on the base for the frame, and scales for indicating the spacing of the axis bearing from the pivot as the position of the frame is adjusted along the guides.
 5. Apparatus for reproducing curved lines including in combination a beam, a pivot, the beam having a slot therein extending lengthwise of the beam and through which the pivot extends in a direction substantially normal to the direction of extent of the slot whereby the beam is movable with respect to the pivot both angularly and in the direction of the length of the beam, a scriber carried by the beam in a position to travel over a work surface as the beam moves with respect to the pivot, a link element connected with the beam, an axis bearing connected with the link element at a location spaced from the connection of the link element to the beam, means for adjusting the spacing of the axis bearing toward and from the pivot, said means for adjusting the spacing including means for holding the axis bearing and the pivot at a fixed spacing from one another after each adjustment, and means for moving the link element angularly about the axis bearing to impart angular and sliding movement to the beam with respect to the pivot.
 6. The apparatus described in claim 5 characterized by the means for moving the link element angularly about the axis bearing being a handle extending upward from the connection of the link element to the beam, the handle being in axial alignment with the angularly movable connection of the link element to the beam.
 7. The apparatus described in claim 5 characterized by means for adjusting the length of the beam between the center points of the scriber and the connection of the link element with the beam.
 8. The apparatus described in claim 5 characterized by the beam being slotted throughout substantially its entire length to provide the sliding movement of the beam in the direction of its length with respect to the pivot and for the adjusTment of the connection of the link element along the length of the beam, and the scriber and the link element being on different sides of the pivot along the length of the beam.
 9. The apparatus described in claim 5 characterized by a frame on which the axis bearing is supported, the link element comprising a disc with a center bearing that rotates on the axis bearing, a block that slides along a slot in the disc, said slot extending in a direction having a radial component, means for clamping the block at desired locations along the slot, the block being a part of the link element that connects with the beam, the disc and frame having a scale on one of them and a position indicator on the other for indicating angular positions of the disc, a base for placing on a support, the pivot being connected with the base as a unitary part thereof, the disc-supporting frame being located on the base and slidable along the base toward and from the pivot, guides on the base for the frame, scales along the guides for indicating the spacing of the axis bearing from the pivot as the position of the frame is adjusted along the guides, the beam being slotted throughout substantially its entire length to provide for sliding movement of the beam in the direction of its length with respect to the pivot and for the adjustment for the connection of the link element along the length of the beam, and the scriber and the link element being on different sides of the pivot lengthwise of the beam.
 10. The apparatus described in claim 9 characterized by the scriber being located near one end of the beam and the scriber end of the beam projecting for a substantial distance from one side of the rest of the apparatus and over a work area larger than the area covered by the base and other parts of said rest of the apparatus. 